The purpose of the proposed research is to use a daily process approach to understand the psychosocial and social cognitive factors related to HIV risk behavior among HIV positive South African individuals. The first phase of the research will involve developing, pilot testing, and refining a structured daily diary to assess stress, affective states, coping, social cognitive factors, substance use, and HIV risk behavior. This diary will be used to collect daily data for 6-weeks from 140 HIV positive individuals. Multilevel Modeling will be utilized to test the proposed association between stress and HIV risk behavior and explore possible mechanisms as to how such a relationship may unfold in HIV positive individuals daily lives. This will result in an understanding of how stressful daily events and an individual's responses to these events ultimately affect HIV risk behavior. This research represents one of the first studies to examine the role of daily stressful events as factor related to HIV risk behavior, and to measure predictors of HIV risk behavior close to real-time. These findings may suggest effective strategies to intervene with HIV positive individuals and to prevent further HIV infections among HIV negative individuals in South Africa. [unreadable] [unreadable]